Diseased mitral and tricuspid valves frequently need replacement or repair of various reasons. The mitral and tricuspid valve leaflets or supporting chordae may degenerate and weaken or the annulus may dilate leading to valve leak (valve insufficiency). The chordae tendinae, or heart strings, in short called the chordae, are cord-like tendons that connect the papillary muscles to the tricuspid valve and the mitral valve in the heart. The leaflets and chordae may become calcified and thickened rendering them stenotic (obstructing forward flow). Finally, the valve relies on insertion of the chordae inside the ventricle. If the ventricle changes in shape, the valve support may become non-functional and the valve may leak.
During heart valve replacement, sutures are spaced around the annulus (the point where the valve leaflet attaches to the heart) and then the sutures are attached to a prosthetic valve, see FIG. 3. The valve is lowered into position and when the sutures are tied, the valve is fastened to the annulus. The surgeon may remove all or part of the valve leaflets before inserting the prosthetic valve.
In heart valve repair, a defective valve is left in situ and surgical procedures are performed to restore its function. Mitral and tricuspid valve repair is traditionally performed with a suture technique, e.g. by performing the so-called Parachute procedure, see FIG. 2.
Heart valve repair and heart valve replacement may be performed in combination, e.g. a dilated leaflet may be partially surgically removed (e.g. leaving the chordae intact) and a heart valve replacement prosthetic valve may be affixed to the surgically modified anatomical heart valve in order to restore heart valve function.
Frequently an annuloplasty ring is used to fixate an altered size of the annulus and/or support the annulus. The annuloplasty ring serves to keep the annulus in a reduced diameter and to allow the existing leaflets to oppose each other normally again, in order to restore correct valve function. Sutures are used to attach the prosthetic annuloplasty ring to the annulus of the heart valve and to assist in plicating the annulus. Before permanently attaching the annulosplasty ring to the annulus, the latter is prepared to the desired shape by other means than the annulosplasty ring. This preparation of the valve in order to achieve a correct geometrical arrangement of the anatomical entities of a heart valve, and a restored correct function thereof, is hitherto performed manually by a surgeon. This part of the procedure is also called downsizing, which is explained in more detail below. Furthermore, manual downsizing may be dependent on a line of sight or suitable imaging modalities.
In addition, the form of the valve leaflets may be corrected by surgical techniques, e.g. tiny sutures, during the same surgical procedure. In general, the annuloplasty ring must be sutured to the valve annulus at the same time as a desired form of the latter is obtained at the end of the procedure. This simultaneous downsizing of the valve annulus and, which is time consuming and tedious. This means that two highly integrated processes are involved in the Parachute procedure, namely a) downsizing, perhaps including reshaping, of a dilated valve and b) a subsequent fixation of an annuloplasty ring. Thus, the Parachute procedure is highly dependent on the experience of the performing surgeon, who has to be able to think sterically, as it is necessary to firstly place the sutures on the annulus and then through the support ring.
A result of such a procedure may differ greatly and even provide a non-desired result, very much depending on the skills of the surgeon performing the procedure. If the ring is severely malpositioned, then the stitches must be removed and the ring repositioned relative to the valve annulus during restitching. In other cases, a less than optimum annuloplasty may be tolerated by the surgeon rather than lengthening the time of the surgery to restitch the ring.
During heart surgery, a premium is placed on reducing the amount of time used to replace or repair valves as the heart is frequently arrested and without perfusion. It would therefore be very useful to have a device and method to efficiently facilitate repair of heart valves or to facilitate attachment of a valve prosthesis into the mitral or tricuspid valve position.
There is a need of improving this downsizing. It would be advantageous to be less dependent on the human factor. Moreover, the surgeons would welcome a device and method facilitating this crucial operation.
In WO2006/054930, which is hereby incorporated by reference in its entirety for all purposes, a device for repairing a heart valve is disclosed that comprises an implantation instrument. The implantation instrument comprises a first support ring, and a second support ring connected to the first support ring to form a coiled configuration. The first support ring is configured to abut one side of the valve and the second support ring is configured to abut an opposite side of the valve to thereby trap a portion of the valve tissue there between. The device further comprises an annuloplasty implant adapted to be attached to the heart valve annulus in order to reshape the annulus and allow the leaflets to open and close properly. The annuloplasty implant is connected to the implantation instrument for insertion to the annulus. The implantation instrument disclosed in WO2006/054930 provides already a major improvement of the previously known devices and methods. However, the devices and methods as disclosed in WO2006/054930 may further be improved as a primary re-shaping for defining a working position of the insertion tool still has to be performed by the surgeon using a forceps instrument. Similar devices, suffering from analogous drawbacks are disclosed in e.g. US 2004/0167620, US 2005/0149178, and WO 2007/030063.
US2007/0038293 discloses methods, devices, and systems for performing endovascular repair of atrioventricular and other cardiac valves in the heart. Regurgitation of an atrioventricular valve, particularly a mitral valve, can be repaired by modifying a tissue structure selected from the valve leaflets, the valve annulus, the valve chordae, and the papillary muscles. These structures may be modified by suturing, stapling, snaring, or shortening, using interventional tools which are introduced to a heart chamber. The tissue structures can be temporarily modified prior to permanent modification. For example, opposed valve leaflets may be temporarily grasped and held into position prior to permanent attachment. However, the disclosure of US2007/0038293 does only provide local modification of certain portions of a heart valve, e.g. by grasping one or more leaflets for bringing these into a position suitable for fixation of a clip to the leaflets. Hence, the motion of the valve leaflets is only partly and temporary immobilized.
In WO 2006/093656 devices and methods are disclosed for aiding valve annulosplasty. The disclosed devices comprise a radiopaque deformable reference ring facilitating imaging based navigation of an annulosplasty procedure. However, the devices are not providing an active downsizing. Downsizing still has to be performed in a separate manner.
Therefore, there is a need to for devices and/or methods that further facilitate heart valve repair and/or replacement, e.g. by providing a suitable annuloplasty preparation of a cardiac valve area.
Thus, there is a need to provide a tool, medical device, or method that provides for a reliable and more easily accomplished valve repair or replacement. Facilitated, or less surgically demanding insertion of an annuloplasty implant and/or artificial heart valve would be advantageous. Hence, an improved tool, medical device or method would be advantageous and in particular a tool or method allowing for increased flexibility, user-friendliness, cost-effectiveness, and/or patient safety would be advantageous.